Unholy actually scales just fine with strength and every secondary stat but crit. It scales terribly with weapon damage, roughly half as well as frost.

Originally Posted by Schizoide

just fine

Key information right here. It scales somewhat okay with strength but not nearly as well as in the past like I mentioned above and certainly not amazingly like Muraza would have you believe. Add in the weapon damage factor and you've got yourself a spec that doesn't scale as well as most other specs and scales horribly badly compared to Frost. This is one of the crippling flaws Unholy has had to deal with since they changed ScS into a single rune ability.

On the other hand, Unholy scales less than half as well with weapon DPS. That is something that I believe should be fixed. Ideally by causing Death Coil to deal a percentage of weapon damage, but there are tons of other ways to fix it too, mostly involving moving damage from secondary attacks back into Scourge Strike.